code: def __call__(self, chunk_size=None):
      if self.size is None:
          shape = (len(self.pvals),)
      else:
          try:
              shape = tuple(self.size) + (len(self.pvals),)
          except TypeError:
              shape = (self.size, len(self.pvals))
      return self.new_tensor(None, shape, raw_chunk_size=chunk_size)
  
file_path: mars/mars/tensor/random/multinomial.py
imports: import numpy
  from ...None import opcodes
  from ...serialization.serializables import FieldTypes, Int64Field, TupleField
  from ..utils import gen_random_seeds
  from .core import TensorRandomOperandMixin, TensorDistribution
label_desc: Use image node_id 1 for calling the TensorMultinomial obj's underlying member method code with example usage: obj.__call__(chunk_size) and returns: self